diff --git a/speeduino/speeduino.ino b/speeduino/speeduino.ino
index a706a6b8..359febb0 100644
--- a/speeduino/speeduino.ino
+++ b/speeduino/speeduino.ino
@@ -209,7 +209,12 @@ void setup()
   loadCalibration();
 
   //Set the pin mappings
-  if(configPage1.pinMapping > BOARD_NR_GPIO_PINS) { setPinMapping(3); } //First time running? set to v0.4
+  if(configPage1.pinMapping > BOARD_NR_GPIO_PINS)
+  {
+    //First time running on this board
+    setPinMapping(3); //Force board to v0.4
+    configPage1.flexEnabled = false; //Have to disable flex. If this isn't done and the wrong flex pin is interrupt attached below, system can hang.
+  }
   else { setPinMapping(configPage1.pinMapping); }
 
   //Need to check early on whether the coil charging is inverted. If this is not set straight away it can cause an unwanted spark at bootup
@@ -270,7 +275,6 @@ void setup()
     }
   }
 
-
   //Check whether the flex sensor is enabled and if so, attach an interupt for it
   if(configPage1.flexEnabled)
   {
@@ -344,7 +348,6 @@ void setup()
   pinMode(pinTrigger3, INPUT);
   //digitalWrite(pinTrigger, HIGH);
 
-
   //Set the trigger function based on the decoder in the config
   switch (configPage2.TrigPattern)
   {
@@ -955,6 +958,7 @@ void loop()
       currentStatus.PW1 = 0;
       currentStatus.VE = 0;
       toothLastToothTime = 0;
+      //toothLastMinusOneToothTime = 0;
       currentStatus.hasSync = false;
       currentStatus.runSecs = 0; //Reset the counter for number of seconds running.
       secCounter = 0; //Reset our seconds counter.
diff --git a/speeduino/utils.ino b/speeduino/utils.ino
index 95db98b1..d7279b91 100644
--- a/speeduino/utils.ino
+++ b/speeduino/utils.ino
@@ -300,13 +300,14 @@ void setPinMapping(byte boardID)
       pinDisplayReset = 48; // OLED reset pin
       pinTachOut = 49; //Tacho output pin  (Goes to ULN2803)
       pinIdle1 = 2; //Single wire idle control
-      pinIdle2 = 3; //2 wire idle control (Note this is shared with boost!!!)
+      pinBoost = 4;
+      pinIdle2 = 4; //2 wire idle control (Note this is shared with boost!!!)
       pinFuelPump = 37; //Fuel pump output  (Goes to ULN2803)
       pinStepperDir = 16; //Direction pin  for DRV8825 driver
       pinStepperStep = 17; //Step pin for DRV8825 driver
       pinFan = 47; //Pin for the fan output (Goes to ULN2803)
       pinLaunch = 12; //Can be overwritten below
-      pinFlex = 2; // Flex sensor (Must be external interrupt enabled)
+      pinFlex = 3; // Flex sensor (Must be external interrupt enabled)
       break;
 
     case 10:
@@ -441,6 +442,9 @@ void setPinMapping(byte boardID)
       pinFan = 47; //Pin for the fan output
       pinFuelPump = 4; //Fuel pump output
       pinTachOut = 49; //Tacho output pin
+      pinFlex = 3; // Flex sensor (Must be external interrupt enabled)
+      pinBoost = 5;
+      pinIdle1 = 6;
       break;
   }